Thomas Lennart Joakim Erikson is a Swedish author. He is known for his self-help book series Surrounded By, more specifically his book, Surrounded by Idiots, in which he categorizes the personalities of people in colors based on the DISC assessment.

A DISC assessment is a pseudoscientific personality testing tool based on psychologist William Moulton Marston’s DISC emotional and behavioural theory, first published in 1928.